Multiple head embroidery machine



Aug'31, 1937- A. A. BOHMANN Er Al. 2,091,727 l MULTIPLE HEAD EMBROIDERY MACHINE Filed Feb. 1e, 1952 2 sheds-sheet 1 ATTORNEY Aug. 3,1, 1937. A. A; BOHMANN Er Al.- 2,091,727 l MULTIPLE HEAD EMBROIDERY MACHINE Filed Feb. 16, 1932 2 Sheets-Sheet 2 Patented Aug. 3l. 1937 UNITED' STATES PATENT oFrici-z l. l. I neaniillzimear t i y t Arthur Ann-eem Scheibel, Dresden,

Hohmannr and Kurt Gustav Germany, Worker, Gesellschaft assignors to mit besohl'ankter Haftung, Dresden, Germany Application February 16,

1932, serial No. 593,231

In Germanyl February 17, 1931 1 Claim. (Cl. i12-102) Y 'I'he present invention relates to improyements in or relating .to multiple head automatic embroidery machines. I s

Multiple head single needle embroidery machines are already known in which the embroidery frames are guided by an embroidery frame displacing device. In'these machines the material to be embroidered is guided on a horizontal plane. Consequently the embroidery frame displacing device has considerable friction to overcome in 'the horizontal plane. Since the weight ofthe displacing device rests on vthe needle plate, the oscillating masses must vbe reduced as far as possible. The whole construction of the multiple head embroidery machine depends 'therefore in the first place on the embroidery frame displacing device.

Attempts have already been made to employ guiding parallelograms with hinge joints, but these constructions have the disadvantage that with the rapid movement ofthe frame necessitated by the high rate of revolution of the machine, the hinge points easily wear out and become useless so that accurate guiding of the embroidery framesbecomes impossible.

In order to avoid oscillating, the individual embroidery frames themselves have been controlled by a displacing device. Each embroidery frame carries an-angle member which is moved by guiding spindles of two component devices of anv automatic machine or the like. This arrangement however is only practicable if the guiding spindles are mounted under the needle plate and the intermediate members which engage the two arms of the angle project through slits in the needle plate. In embroidering the material however the disadvantage is presented that the may terial very easily enters there. l

The present invention has for its object to re- ,move all these disadvantages of multiple head automatic embroidery machines by a new and stable embroidery frame guiding means the mass of which can be reduced to a minimum and which necessitates a special arrangement of the embroidery machine heads. V

According to the present invention we provide a multiple head automatic embroidery machine having-an embroidery framey carrier which is moved by a component mechanism working in the slits and gets caught two directions at right angles characterized inA that the means for. connections of the component mechanism on the embroidery frame carrier' are formedas sliding or roller guides. I

In order that the invention may be well unlates about a fixed derstood preferred embodiments thereof will be described by way of example with reference to the accompanying drawings in which:

Figure 1 is a diagrammatic plan view of an embroidery machine having an embroidery frame guiding means comprising a rigid angle, showing the embroidery machine heads. y

- Figure 2 is a diagrammatic plan view of an embroidery machine having a frame like closed guiding means and showing the embroidery machine heads.

Figure 3 is a' sectional elevation showing the arrangement for adjusting the embroidery machine heads. y

Fig. 4 is a detail view of the embroidery frame holders and their co-operatlng parts on an en.- lar'ged scale.

. Fig. 5 is a sectional elevation thereof.

Fig. 6 is a detail view of a coupling. r

Referring to Figure 1 of the drawings embroidery machine heads I, II and III each preferably formed like that of a sewing machine, are arranged at equal distances apart. The heads are each provided with an arm I which carries at its forward end a vertically reciprocating needle 2y as shown in Figure 3. The foot 3 of the head ls secured to a base plate 4 over which the material is moved. The drive ofthe multiple head embroidery machine is effected by means of the belt wheel 5 which drives the first embroidery machine head I and the other two heads II and III y by means of a coupling shaft 6, 6' and bevel gears.

Apart from this intermediary of matic mechanism known component mechanisms a for producing horizontal direction and b for the vertical direction (i. e. vertical referring to Figure 1 of the drawings but actuallyV horizontal). Racks l and 8 are driven by the mechanisms a and b and are guided in bearings '9 and i0. The rack 1 has a sliding or rolling. guide II in which a short rod like arm I2 engages gle with a long arm I3 and a connecting strut I4. The other rack 8 for the vertical direction engages forwardly by means of its head I5 with a bell crank lever I6.which oscillates about a fixed pivot I1. The extended arm is connected through the hinges 20 and a linkl with'a secondpbell crank lever i9 of equal size, which likewisev oscilpivot 26. BothA pivots I1 and 26 must therefore be the samey distance apart as the length of thelink I8 between-the hinges 20. The two short arms 2| of the bellcrank levers engage in the guides -22 of two slides 23 and which forms a rigid anholders 28 are ilxedly connected with the arm which are guided parallel to each other in bearings 24. Each slide carries at its forward end a sliding or roller guide 25 which embraces the long arm I3 of the rigid angle member I2, I3.

According to the motion of the two racks 1 and.

8 by the component mechanisms a and b the angle member I2, I 3 is moved horizontally by the' action `on the short arm I2 and vertically by the action on the long arm I3. If for example the rigid angle4 member is moved in the horizontal direction by the rack 1, the two slides 23 which engage the long arm I3 merely serve to guide the angle member in a straight line. If the rack 8 is moved by the component mechanism b of the automatic mechanism the movement is transmitted to the parallel slides 23 by the bell crank levers I6 and I9.

For the sake of convenience of operation the embroidery frames 21 are disposed forwardly on the needle plate of the machine. Each emV broidery frame is carried by two embroidery frame holders 28. All of the embroidery frame I3 of the embroidery frame guiding means. The arm I3 which is adapted to be slidably guided is therefore the carrier arm for the frames and preferably lies between the foot 3 and the needle 2 of each embroidery machine head (Figure 3). If for example more than three embroidery machine heads are arranged adjacent one Ianother then the arx'n I3 of the embroidery frame guiding means must be extremely long. In order that the arm may possess sufiicient strength and will not bend or oscillate when in use it must be made correspondingly wide. Consequently the rspace for y' the embroidery frame between the foot 3 of the embroidery machine head and the needle 2 becomes too small or narrow and the arm I of the embroidery machine head must be considerably increased in length. In order to avoid thisit is advantageousto adopt a different arrangement of the embroidery frame guiding means as shown in Figure 2.

For the sake of simplicity the arrangement is likewise shown as having three embroidery machine heads. As in the first example the embroidery machine heads are driven by means of the belt wheel 5 through bevel gears and the coupling shaft 6, 6. In addition to this the auto- -matic mechanism A is driven by means of the belt wheel 5 and comprises two component mechanisms a for the horizontal direction and b for the vertical direction (referring of course to the horizontal and vertical directions of Figure 2 of the drawings). Racks 'I and 8 are driven from the component mechanisms, the two racks being guided in bearings 9 and I0. The rack 1 for providing the horizontal motion engages with' its slide or roller guideway II which in this case is disposed at the forward end of the rack 'I with a small rod-like arm I2 which forms a rigid angle with the long arm 29 which is utilized as a straight line guiding means. The angle member so formed is closed by means of a connecting strut 30 and a carrier bar 3i for the embroidery frames to form a rigid quadrilateral frame. Struts 32 serve for stiiening the angles of the quadrilateral frame. The foot 3 of one or more of the embroidery machine heads project through this quadrilateral frame, but as shown in Figure 2 this only applies to the machine head Il. If the machine includes more embroidery machine heads the quadrilateral frame is elongated and is strengthened bymeans of a plurality of connecting struts 30 so that the frame forms a, rigid carrier in the form of a `utilized in this casevand for this purpose the arm 29 of the embroidery frame guiding means is constructed of light metal. 'I'his carries at each end guide rails 33 made of steel on which guide blocks 34 of bell crank levers 35 and 36 slide. 'I'he two bell crank levers oscillate about fixed pivots 31 and carry pivots 39 at the end of longer arms to which pivots the connecting 40 is hinged. The rack 8 engages with its 4I which is formed as a sliding or roller link head their Y guide'.

member. with the bell crank lever 35 and thereby moves the guiding frame in a vertical direction.v The guiding in a straight line of the embroidery" frame guiding means in this case is eiected di- 'rectly by the two bell crank levers. Also -in this .case the linear guiding is dependent upond the distance of the bell crank levers. In order to save weight ythe carrier bar 3| i'or the rst and last embroidery machine heads I and III is extended at both sides of the forward corners of the quadrilateral frame so that the embroidery frames for the corresponding machine heads can be fixed to the free ends of the carrier bar 3|. By this arrangement it is possible to avoid the use of further connecting struts 30 at the ends because 'the car?l Y rier bar 3| is in itself of such strength that the free ends possess sufficient rigidity.- In this way considerable Weight is saved.

The carrier bar 3I need not be directly the carrier for the embroidery frame holders. In the example described with reference to Figure 2 two guide bearings 42 and 43 are arranged on the ends of the carrier bar 3l in which a round embroidery frame rod 44 is guided on which the embroidery frame holders 45 and 46 are iixed. Whilst the bearing 42 merely serves as a guide the lbearing 43 is provided with a clamping screw 41 by means of which the embroidery frame rod 44 can be held xed. This whole arrangement has the advantage that the embroidery frame ro'd 44 with the frame holders and the frames can be shifted in the guides 42 and 43. This is particularly important if greater areas of material are to be embroidered than the normal areas for which the machine is normally employed. In this case the method of displacement as described in German Patent specication No. 469,261 can be adopted. Apart from this this arrangement has the advantage that the embroidery frame rod together with the frame holders and the frames can be swung upwardly. Thus without removing the frames the lower side of the embroidery can be inspected. It is also possible so to fix the embroidery frame rod by means of the clamping screw 41 that the frames rest very lightly on their under surfaces. embroidery frame holders 45 and 46 can therefore be constructed of resilient material and the points ofA attachment for the frames can lie in the ,medial axis of the frames. As shown in Figures 4 and 5, each of the frames 50 has at both of its sides a fastening strip 49, each in The slot 53 of holder 46 rying a threaded socket a. 'The holder 46 has a laterally extending slot 53, while holder 45 has a longitudinally extending slot 54. The frame 50 is slid beneath the holders and is secured by means of screws b to its holders. If now for instance the screw b of the right hand holder 45 is loosened, the frame 50 can be inwardly moved in the slot 54 so that upon loosening screw b at the left hand the frame can be moved at the so asvto allow a regulation of the material within certain limits. This. of course, pertains only to the opposite end frames, as the holders 46 are all provided with laterally extending slots.

If the frames 50 are all tensioned then these form with the embroidery frame holders 45 and i6 and the embroidery frame rod 44 a rigid framework which permits no oscillation of the frames. The fact that the carrier bar for the frames is arranged as a special embroidery frame rod 44 on the embroidery frame guiding means and is exchangeable by being withdrawn from the guides 42 and 43 has the advantage that other larger frames can be employed for embroidery which are themselves xed to a separate rod. The driven shaft 6' can be uncoupled from the driving shaft 6, carrying the embroidery head II, by the retraction of bolt d to uncouple members 5I, 52 of the coupling. Bolt d iskept in its retracted position by any well known means employed for this purpose. The distance between the heads can be varied due to the squared shaft sections as illustrated in Figure 3.

With the multiple head automatic embroidery machine according to the embodiment described in the example it is also possible to embroider overlaid work. All three embroidery machine heads then embroider simultaneously in a common frame. By means of the above described 40 enlargement of the embroidering area by displacement the individual designs can be arranged one over the other to an overlaid design. The size of the design must then always be a multiple of the distance apart of the embroidery machine 45 heads. In order not to be bound by the size of 50 brackets is shown in Figure the design it is advantageous to be able to adjust the embroidery machine heads II and III. For this purpose the flat base plate 4 carries two brackets 55 for each head (only one pair of such 3 for head I as an example) which serve as threaded guides in which two adjusting rods 56 engage. Each head can be adjusted by means of the two adjusting rods so that the distance from needle to needle of the individual heads can be diminished or increased. The embroidery machine heads II and III rest with their base plates 4 on two longitudinal angle members 51` which serve as guide rails and at the same time as carriers for the embroidery machine heads. Since the embroidery machine heads must work in time with one another it is necessary that between the individual bevel gears in the heads and also in the individual couplings 5I and 52 and the coupling shaft 66' there shall be no back las The embodiments of the present invention illustrated and claimed in the appended claim are not merely applicable to automatic embroidery machines but also to multiple head embroidery machines which are operated by hand by means of pantographs. Moreover it is to be understood that Various modifications may be made without departing from the scope of this invention.

Having now particularly described and ascertained the nature of our said invention and in what manner the saine is to be performed, we declare that what we claim is:

In a multiple head embroidery machine including embroidery frames, means for guiding said frames, said means comprising a carrier bar, guide bearings at the ends of said carrier bar, a frame supporting rod supported in said guide bearings for longitudinal adjustment therein, means for retaining said rod in adjusted -position relatively to the carrier bar, resilient embroidery frame holders carried by said rod at the ends thereof and intermediate the ends and extending laterally of the rod in longitudinally spaced relation therealong, the intermediate holders beingA provided with lateral slots adjacent their free ends, and the end holders being provided with longitudinal slots adjacent their free ends, fastening strips secured to the frames, means carried by the free ends of the fastening strips for securing same to the holders with capacity for angular adjustment of the fastening strips of the end frames, means for uncoupling one of the embroidery heads from the rest, and

means to vary the distance between the heads.

ARTHUR ALBRECHT BOHLIANN. KURT GUSTAV SCHEIBEL. 

